The scattering of elastic waves in a medium with damage from microcracking is discussed. The influence of damage from penny-shaped microcracks within a homogeneous medium is considered. The microcracks are assumed to be randomly oriented and uniformly distributed. Explicit expressions are derived for the attenuation of longitudinal and shear elastic waves in terms of the damage parameter and th...

Introduction: In laser surgery, the laser beam can evaporate and cut the tissue like a small surgical knife when the tissue temperature is heated to 100 degrees Celsius. a complete understanding of the distribution of damage in both pathologic tissue and surrounding tissue is necessary. Although the test is the most realistic solution for treating medical problems, for this rea...

On 16th of March 2008, temperature decreased to -6ºC in some parts of the Kerman pistachio plantation area that was caused the heavy damage to pistachio growers. After the damage, some rootstocks were resistance to this temperature and no damage was interned to them. In the present study five rootstocks of resistant and five rootstocks of susceptible to frost damage were selected and evaluated ...

In previous work, we developed an 8-state nonlinear dynamic model of the acute inflammatory response, including activated phagocytic cells, pro- and anti-inflammatory cytokines, and tissue damage, and calibrated it to data on cytokines from endotoxemic rats. In the interest of parsimony, the present work employed parametric sensitivity and local identifiability analysis to establish a core set ...

In this study, the effect of earthquake frequency content and noise effects on damage detection has been investigated. For this purpose, the damage was defined as nonlinear behavior of beams and columns, and several ground motion records were scaled so that some elements yield under the applied excitation. Then the acceleration response data of each floor obtained using the nonlinear dynamic an...

Deterministic forecast of corrosion damage progression in a reinforced concrete column was implemented in a one-dimensional model accounting for potential dependence of corrosion threshold, and macrocell coupling during the initiation and propagation stages. The damage projection was clearly sensitive to the choice of the activation zone size. The relative sensitivity became greater as the zone...

This study proposes a fault detection and diagnosis method for bearing systems using ensemble empirical mode decomposition (EEMD) based feature extraction, in conjunction with particle swarm optimization (PSO), principal component analysis (PCA), and Isomap. First, a mathematical model is assumed to generate vibration signals from damaged bearing components, such as the inner-race, outer-race, ...

Study the tensile damage and fracture behavior of FRP composite materials by the acoustic emission technology, broadband sensors record the acoustic emission signals when composite materials in the process of tensile damage at different fiber angle. The acoustic emission characteristics of FRP composite materials’ tensile damage was analyzed by 3D parameter methods. Analysis the amplitude of co...

In this contribution an algorithm for parameter identification of gradient enhanced damage models is proposed, in which non-uniform distributions of the state variables such as stresses, strains and damage variables are taken into account. To this end a least-squares functional consisting of experimental data and simulated data is minimized, whereby the latter are obtained with the Finite-Eleme...